Understanding the effects of undernutrition and RED-S on athletic performance

Beyond the Limit: Understanding the Damage Caused by Underfueling and RED-S to Athletic Performance

RED-S (Relative Energy Deficiency in Sport) is a medical condition caused by insufficient energy intake relative to the high energy expenditure associated with intense physical activity. It goes beyond simple underfueling, affecting various body systems, including metabolism, the hormonal system, bones, muscles, and immune function. Detecting and treating RED-S promptly is crucial to prevent potentially serious complications in athletes. Previously, the scientific literature referred to the “female athlete triad,” which encompassed the combination of intensive athletic activity, amenorrhea (absence of periods for more than 3 months), and insufficient food intake relative to energy expenditure. This syndrome is no longer limited to women; men are also affected, particularly in endurance sports.

1) Understanding Underfueling and RED-S: Insidious Threats

For a long time, thinness in sport was associated with good health. In weight-category sports, athletes sometimes need to lose weight and restrict their intake to reach a lower category and compete against different opponents. In endurance sports such as cycling, athletics, and triathlon, weight plays a crucial role because it is correlated with power per kilogram. However, a lack of strength is much more problematic than actual weight, as we will see below.

We also often use the familiar phrase, “He or she is lean.” Here, leanness refers to the athlete’s weight, implying that he or she is lean and will therefore perform well—but that is not how it works. The term “sharpened” is originally used in an athlete’s preparation cycle. The tapering period is the period just before competition during which the athlete rests while maintaining the intensity specific to their competition in order to perform well.

The goal for athletes is to find the delicate balance between managing body weight and maintaining power. Often, the athlete’s aim is to lose weight, but sometimes the deficit occurs without their knowledge. They may think they are eating enough because the amount of food on their plate is substantial, but their macronutrient intake is poorly balanced. We also need micronutrients, and excluding certain foods can work against us.

To learn more about the dangers of underfueling and RED-S, download our free e-book containing the full article HERE.